Thanks, Iceblue for this question as I have often thought Hank has panic attacks throughout this series and pondered the same question what if Hank DID find out Walt is Heisenberg. Same question goes for if Walt Jr. finds out his dad is Heisenberg too. The last two points would be a real problem for Hank..."After finding Walt is Heisenberg" AND "Trying to hide that he found Walt is Heisenberg". Walt is "family" and how can Hank turn in a family member to the DEA? Could Hank be so cold blooded to turn in his brother-in-law???

OR Hank does turn in Walt but explains the circumstances of Walt's extreme behavior, i.e.. having terminal cancer, trying to pay the bills and save his family from financial ruin with the hopes the Feds sympathize with Walt's dilemma and give him a reduced sentence.